J.G. Castano

Remote system for patient monitoring using Bluetooth/spl trade/

The aim of this study is to design and develop a low-power wireless A/D-converter that should be easy to integrate with other technologies or infrastructures at a low cost. This transmitting unit should be able to replace many of the signal wires between biomedical sensors connecting the patient and the sampling unit or supervision equipment. The model of today is an embedded hardware solution with two processors (FPGA and Bluetooth). A twelve bit ADC with a 1 kHz-sampling rate then converts an analogue signal that simulates an ECG-signal with typical frequencies. The communication between the ADC and Bluetooth/spl trade/ is serial and controlled by the FPGA. The remote PC runs a simple software that controls the Bluetooth/spl trade/ and processes the received data. The results indicate that it is possible to continuously transmit an ECG-signal without losing data.

Steps towards a minimal mobile wireless Bluetooth/sup TM/ sensor

This paper describes a new Bluetooth/sup TM/-based wireless implementation of a mobile sensor. The solution reduces dramatically both power consumption and size of a wireless sensor improving earlier Bluetooth/sup TM/ implementations where multi-chip solutions were used and mobility was not supported. Three different implementations from multi-chip to single chip are described with the sensor wireless interface, the architecture, protocols and algorithms used. Achieved results are: (1) Implementation of 1 chip solution wireless sensor using the internal Bluetooth/sup TM/ module ADC for external sensing purposes. (2) Mobile sensor wireless monitoring with Bluetooth/sup TM/.

Optimization of wireless Bluetooth sensor systems.

Within this study, three different Bluetooth/spl trade/ sensor systems, replacing cables for transmission of biomedical sensor data, have been designed and evaluated. The three sensor architectures are built on 1-, 2- and 3-chip solutions and depending on the monitoring situation and signal character, different solutions are optimal. Essential parameters for all systems have been low physical weight and small size, resistance to interference and interoperability with other technologies as global- or local networks, PCs and mobile phones. Two different biomedical input signals, ECG and PPG (photoplethysmography), have been used to evaluate the three solutions. The study shows that it is possibly to continuously transmit an analogue signal. At low sampling rates and slowly varying parameters, as monitoring the heart rate with PPG, the 1-chip solution is the most suitable, offering low power consumption and thus a longer battery lifetime or a smaller battery, minimizing the weight of the sensor system. On the other hand, when a higher sampling rate is required, as an ECG, the 3-chip architecture, with a FPGA or micro-controller, offers the best solution and performance. Our conclusion is that Bluetooth/spl trade/ might be useful in replacing cables of medical monitoring systems.

Bluetooth energy characteristics in wireless sensor networks

In this paper a measurement system to create an experimental model and a tool box for simulations concerning both the energy consumption and the time aspect when creating wireless sensor networks using Bluetooth 2.0 + enhanced data rate has been developed. Further energy and time characteristics for critical events when using Bluetooth 2.0 in wireless sensor networks are investigated experimentally, with the main events; create connection, send data, receive data, and idle state. Results show that when allowing higher latencies for the connection in the Wireless Sensor Networks the power consumption drops drastically when using low power mode as sniff.

Local positioning for wireless sensors based on Bluetooth/spl trade/

Self-organizing sensor networks are one of the systems that would benefit from the new local positioning features offered by the new generation of wireless technologies. Location dependent sensor data transfers could be optimized by means of local positioning services. Many start-up companies have available proprietary positioning systems meeting the unique requirements of each application. Therefore, the use of a standard like Bluetooth/spl trade/ is a step towards a universal solution. Our system provides location services for mobile industrial and biomedical Bluetooth/spl trade/ -enabled sensors. The RSSI distance estimation, together with a GPS-like triangulation algorithm, lead to a 3 m error positioning system with remote and self positioning topologies. A real time positioning tracking system for one mobile sensor is provided in this article.

Wireless ECG Network

This paper presents a time synchronized wireless ECG sensor network with reliable data communication. Wireless ECG systems are a popular research area where several research groups have presented point-to-point solutions. Alongside the wireless ECG research, the wireless sensor network research has created an increasing interest for secure, low power and predictable network applications. Combining these research areas is a natural step for the evolution of secure wireless monitoring of physiological parameters. In this study the Bluetooth radio standard has been chosen for its versatility. This paper focuses on both the hardware and the software development for a functional multihop ECG network using Bluetooth. The presented wireless ECG network is reliable up to link loss and is easily configured to send more or different types of signals. The system has been tested and verified for secure multihop communication.

Optimization of wireless Bluetooth

Within this study, three different Bluetooth/spl trade/ sensor systems, replacing cables for transmission of biomedical sensor data, have been designed and evaluated. The three sensor architectures are built on 1-, 2- and 3-chip solutions and depending on the monitoring situation and signal character, different solutions are optimal. Essential parameters for all systems have been low physical weight and small size, resistance to interference and interoperability with other technologies as global- or local networks, PCs and mobile phones. Two different biomedical input signals, ECG and PPG (photoplethysmography), have been used to evaluate the three solutions. The study shows that it is possibly to continuously transmit an analogue signal. At low sampling rates and slowly varying parameters, as monitoring the heart rate with PPG, the 1-chip solution is the most suitable, offering low power consumption and thus a longer battery lifetime or a smaller battery, minimizing the weight of the sensor system. On the other hand, when a higher sampling rate is required, as an ECG, the 3-chip architecture, with a FPGA or micro-controller, offers the best solution and performance. Our conclusion is that Bluetooth/spl trade/ might be useful in replacing cables of medical monitoring systems.

Wireless industrial sensor monitoring based on Bluetooth/spl trade/

We describe a novel Bluetooth/spl trade/-based wireless solution for industrial sensor monitoring. The solution enables wireless monitoring systems improving earlier Bluetooth/spl trade/ implementations where mobility is not supported. A distributed wireless sensor network is described with the sensor wireless interface, the architecture, protocols and algorithms used. Achieved results are: (1) Multimobile wireless sensor monitoring with Bluetooth/spl trade/. (2) Deployment of a distributed architecture for wireless sensors with global access.

Optimization of wireless Bluetooth/spl trade/ sensor systems

Within this study, three different Bluetooth/spl trade/ sensor systems, replacing cables for transmission of biomedical sensor data, have been designed and evaluated. The three sensor architectures are built on 1-, 2- and 3-chip solutions and depending on the monitoring situation and signal character, different solutions are optimal. Essential parameters for all systems have been low physical weight and small size, resistance to interference and interoperability with other technologies as global- or local networks, PCs and mobile phones. Two different biomedical input signals, ECG and PPG (photoplethysmography), have been used to evaluate the three solutions. The study shows that it is possibly to continuously transmit an analogue signal. At low sampling rates and slowly varying parameters, as monitoring the heart rate with PPG, the 1-chip solution is the most suitable, offering low power consumption and thus a longer battery lifetime or a smaller battery, minimizing the weight of the sensor system. On the other hand, when a higher sampling rate is required, as an ECG, the 3-chip architecture, with a FPGA or micro-controller, offers the best solution and performance. Our conclusion is that Bluetooth/spl trade/ might be useful in replacing cables of medical monitoring systems.